The present invention relates to a transmission for a wheelchair, and more specifically, to a transmission for a wheelchair capable of selecting manual and motor-driven ways.
Typically, the wheelchair is provided with a ring-shaped driving wheel (or a wheel for a handle grip) on the outsides of the both wheels thereof, respectively, which is rolled and moved by using the hand of a user.
The conventional wheelchair does not have any problem in rolling and moving by the hands of the user, but it is found that it is not convenient for those who are difficult to use and move the wheelchair in a manual way. To solve this problem, a variety of transmission wheelchairs capable of being driven in a motor-driven way are developed.
However, the conventionally developed transmission wheelchairs have the defects that the transmission is configured in a complicated manner and the weight thereof is substantially heavy, such that it is greatly restricted to the user such as a disabled person. Moreover, the conventional transmission wheelchairs are used exclusively for the motor-driven way, and upon demand of use in the manual way, they are inconvenient to change to the desired manual way. Actually, due to the heavy weight of the transmission, it is impossible to use the manual way.
An object of the invention is to provide a transmission for a wheelchair capable of providing a simple construction and all conveniences in use, providing a unit for freely selecting manual and motor-driven ways, making the weight thereof substantially light to thereby prevent the occurrence of the inconvenience in use caused due to the weight of the transmission when in the manual way, and improving the durability thereof and the reliability of operation.
To achieve this and other objects of the present invention, according to the present invention, a transmission for a wheelchair which is installed on a frame for the wheelchair and for selecting and driving the wheelchair in manual and motor-driven ways, which includes: a transmission unit installed on the wheelchair for driving the wheelchair; a clamping unit for fixing the transmission unit on the wheelchair; and a switching unit for switching the wheelchair in the manual and motor-driven ways; wherein the transmission unit comprises, driving rollers coupled to accelerator and decelerators connected to motors on the both sides of the interior of a casing, for driving both wheels, and a controller circuit-connected to the motors, a motor control circuit unit and a battery, for adjusting the transmission unit, wherein the switching unit comprises, a fixing clip assembled by means of the clamping unit with the casing of the transmission unit and having a locking projection locked or unlocked to/from a locking hole of a fixing part fixed on the frame of the wheelchair, a locker elastically coupled with first and second springs on the top and bottom portions of the interior of the fixing clip and for pulling upward by means of a handle, the locking projection elastically protruded on the both sides of the locker, respectively and locked or unlocked to/from the locking hole of the fixing part, a first pulling string connected to a push button elastically installed by means of a third spring on the handle, for pulling the locker with the locking projection by the pressing operation of the push button, to thereby isolate the driving rollers on the both sides of the transmission unit from the wheels, and a ratchet for controlling the manipulation of the handle by means of a stopper connected by a second pulling string to the push button of the handle.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.